1. Field of The Invention
The present invention relates to an electrical connector, and more particularly to a board-to-board matrix-type electrical connector for transmitting both low and high frequency signals as well as large power currents between a mother board and a corresponding daughter board.
2. The Prior Art
The expansion of a computer's memory and capability is often achieved through the addition of expansion cards (also referred to as daughter boards) electrically connected to a mother board of the computer. The daughter board can be connected to the mother board by means of a vertical card connector which has one surface mounted to the mother board and receives an edge of the daughter board in a slot defined in another surface thereof so that the daughter board is positioned perpendicular to the mother board when electrically engaged therewith. Alternatively, a horizontal card connector can be used to parallel the two printed circuit boards thereby promoting a more efficient use of space.
Alternatively, another approach is so-called board-to-board connector assembly which commonly consists of a plug connector portion mounted to a bottom surface of the daughter board and a receptacle connector portion mounted on a top surface of the mother board using well-known surface mounting techniques. The plug and receptacle connector portions are then mated together for transmitting signals between the two printed circuit boards. Since the conventional board-to-board connector requires soldering of each connector portion onto a corresponding printed circuit board before the portions are mated together, manufacture and assembly thereof becomes laborious as well as time and cost inefficient. Furthermore, such a mated connector may result in poor transmission of high frequency signals.
Moreover, conventional connectors also require the positioning of grounding pins between signal pins for reducing ground bounce and cross talk therebetween during high speed signal transmission, thus increasing the total number of pins and the corresponding space. In addition, such a conventional connector does not provide the daughter board with access to a power supply, rather, power cables connect the daughter board with the power supply via the mother board further complicating the assembly thereof. Therefore, an improved connector is required which can overcome the drawbacks of the prior art connectors.